Microplastics/nanoplastics released from facemasks as contaminants of emerging concern.

Facemasks have become a global medical necessity and are a key preventive measure against COVID-19. Typically, facemasks (FMs) are fabricated from non-renewable polymers, particularly polypropylene (PP) and polyethylene (PE), which release secondary microplastic (MPs) due to the chemical, physical, and biological processes. In light of the widespread usage and improper disposal of single-use facemasks, there is concern about their environmental impact since they contribute to plastic pollution during and after pandemics. The repercussions of this have led to millions of tons of plastic waste being dumped into the environment. Due to lack of awareness and improper disposal, the occurrence of micro/nanoplastics released from facemasks in wastewater treatment plants and landfills poses a concern. Infiltration of wastewater treatment processes by micro/nanoplastics at various levels can be problematic because of their chemical nature and broad but small size. Thus, operational and process stability issues can arise during wastewater treatment processes. In addition, landfilling and illegal waste disposal are being used to dispose of potentially infectious COVID-19 waste, leading to an environmental threat to animal and human health and exacerbating plastic pollution. This paper reviews the fate of facemasks in the environment and the repercussions of improper waste management of facemasks in wastewater treatment plants, landfills, and ultimately the environment.

Different weathering conditions affect the release of microplastics by masks.

A generation of microplastics caused by improper disposal of disposable masks has become a non-negligible environmental concern. In order to investigate the degradation mechanisms of masks and the release of microplastics under different environmental conditions, the masks are placed in 4 common environments. After 30 days of weathering, the total amount and release kinetics of microplastics released from different layers of the mask were studied. The chemical and mechanical properties of the mask were also discussed. The results showed that the mask released 25141±3543 particles/mask into the soil, which is much more than the sea and river water. The release kinetics of microplastics fit the Elovich model better. All samples correspond to the release rate of microplastics from fast to slow. Experiments show that the middle layer of the mask is released more than the other layers, and the amount of release was highest in the soil. And the tensile capacity of the mask is negatively correlated with its ability to release microplastics in the following order, which are soil > seawater > river > air > new masks. In addition, during the weathering process, the C-C/C-H bond of the mask was broken.

A first report on the spatial and temporal variability of microplastics in coastal soils of an urban town in south-western India: Pre- and post-COVID scenario.

We present a first study on the temporal changes (2019-2021) in the microplastic abundance in the coastal soils of an urban town in the south-western part of India. All sampling stations exhibited higher abundances of microplastics in soils collected during 2021 (959.7 ± 277.7 particles/kg) compared to those collected in 2019 (515.1 ± 182.7 particles/kg). Morphologically, flakes, fibres, and films are the most abundant types documented in the soil environment. The microplastics of 0.3-5 mm size are relatively more abundant (60.6 %) compared to those of 0.03-0.3 mm size (39.4 %) in 2021. The three main types of polymers (polypropylene and high- and low-density polyethylene) in the soil exhibited an increase in abundance during an interval of 15 months (October 2019 to March 2021). In addition to packaging materials, the enhanced use of surgical masks during the COVID-19 period might have acted as a source of microplastic contamination in the soils.

Occurrence and risks of microplastics in the ecosystems of the Middle East and North Africa (MENA).

The ubiquitous nature of microplastics (MPs) in nature and the risks they pose on the environment and human health have led to an increased research interest in the topic. Despite being an area of high plastic production and consumption, studies on MPs in the Middle East and North Africa (MENA) region have been limited. However, the region witnessed a research surge in 2021 attributed to the COVID-19 pandemic. In this review, a total of 97 studies were analyzed based on their environmental compartments (marine, freshwater, air, and terrestrial) and matrices (sediments, water columns, biota, soil, etc.). Then, the MP concentrations and polymer types were utilized to conduct a risk assessment to provide a critical analysis of the data. The highest MP concentrations recorded in the marine water column and sediments were in the Mediterranean Sea in Tunisia with 400 items/m3 and 7960 items/kg of sediments, respectively. The number of MPs in biota ranged between 0 and 7525 per individual across all the aquatic compartments. For the air compartment, a school classroom had 56,000 items/g of dust in Iran due to the confined space. Very high risks in the sediment samples (Eri > 1500) were recorded in the Caspian Sea and Arab/Persian Gulf due to their closed or semi-closed nature that promotes sedimentation. The risk factors obtained are sensitive to the reference concentration which calls for the development of more reliable risk assessment approaches. Finally, more studies are needed in understudied MENA environmental compartments such as groundwater, deserts, and estuaries.

Simultaneous removal of microplastics and benzalkonium chloride using electrocoagulation process: statistical modeling and techno-economic optimization.

Microplastics and benzyldimethyldodecylammonioum chloride (DDBAC) enter the environment more frequently during the COVID-19 pandemic and their co-occurrence will be a potential threat to the environment in the post-pandemic era. This study investigates the performance of an electrochemical system for the simultaneous removal of microplastics and DDBAC. During experimental studies, effects of applied voltage (3-15 V), pH (4-10), time (0-80 min), electrolyte concentration (0.01-0.0.09 M), electrode configuration, and perforated anode were investigated to identify their influence on DDBAC and microplastics removal efficiency. Eventually, the techno-economic optimization yielded to evaluate the commercial feasibility of this process. The central composite design (CCD) and analysis of variance (ANOVA) are employed for evaluation and optimization of the variables and response, DDBAC-microplastics removal, and for determining the adequacy and significance of mathematical models proposed by response surface methodology (RSM). Experimental results indicate that optimum conditions are pH = 7.4, time = 80 min, electrolyte concentration = 0.05 M, and applied voltage = 12.59, in which the removal of microplastics, DDBAC, and TOC reached the maximum level, which was 82.50%, 90.35%, and 83.60% respectively. The results confirm that the valid model is adequately significant for the target response. Overall, financial and energy consumption analyses confirmed that this process is a promising technology as a commercial method for the removal of DDBAC-microplastics complexes in water and wastewater treatment.

Tracing the Century-Long Evolution of Microplastics Deposition in a Cold Seep.

Microplastic (MP) pollution is one of the greatest threats to marine ecosystems. Cold seeps are characterized by methane-rich fluid seepage fueling one of the richest ecosystems on the seafloor, and there are approximately more than 900 cold seeps globally. While the long-term evolution of MPs in cold seeps remains unclear. Here, how MPs have been deposited in the Haima cold seep since the invention of plastics is demonstrated. It is found that the burial rates of MPs in the non-seepage areas significantly increased since the massive global use of plastics in the 1930s, nevertheless, the burial rates and abundance of MPs in the methane seepage areas are much lower than the non-seepage area of the cold seep, suggesting the degradation potential of MPs in cold seeps. More MP-degrading microorganism populations and functional genes are discovered in methane seepage areas to support this discovery. It is further investigated that the upwelling fluid seepage facilitated the fragmentation and degradation behaviors of MPs. Risk assessment indicated that long-term transport and transformation of MPs in the deeper sediments can reduce the potential environmental and ecological risks. The findings illuminated the need to determine fundamental strategies for sustainable marine plastic pollution mitigation in the natural deep-sea environments.

Impact of the Covid-19 pandemic on microplastic abundance along the River Thames.

In April 2020, the Covid-19 pandemic changed human behaviour worldwide, creating an increased demand for plastic, especially single-use plastic in the form of personal protective equipment. The pandemic also provided a unique situation for plastic pollution studies, especially microplastic studies. This study looks at the impact of the Covid-19 pandemic and three national lockdowns on microplastic abundance at five sites along the river Thames, UK, compared to pre-Covid-19 levels. This study took place from May 2019-May 2021, with 3-L water samples collected monthly from each site starting at Teddington and ending at Southend-on-Sea. A total of 4480 pieces, the majority of fibres (82.1 %), were counted using light microscopy. Lockdown 2 (November 2020) had the highest average microplastic total (27.1 L-1). A total of 691 pieces were identified via Fourier Transform Infrared Spectroscopy (FTIR). Polyvinyl chloride (36.19 %) made up the most microplastics identified. This study documents changes in microplastic abundance before, during and after the Covid-19 pandemic, an unprecedented event, as well as documenting microplastic abundance along the river Thames from 2019 to 2021.

Unmasking effects of masks: Microplastics released from disposable surgical face masks induce toxic effects in microalgae Scenedesmus obliquus and Chlorella sp.

During the COVID-19 pandemic billions of face masks were used since they became a necessity in everyone's lives. But these were not disposed properly and serve as one of the most significant sources of micro and nano plastics in the environment. The effects of mask leached plastics in aquatic biota remains largely unexplored. In this work, we quantified and characterized the released microplastics from the three layers of the mask. The outer layer of the face mask released more microplastics i.e., polypropylene than middle and inner layers. We investigated and compared the acute toxic effects of the released microplastics between Scenedesmus obliquus and Chlorella sp. The results showed a decrease in cell viability, photosynthetic yield, and electron transport rate in both the algal species. This was accompanied by an increase in oxidative stress markers such reactive oxygen species (ROS) and malondialdehyde (MDA) content. There was also a significant rise of antioxidant enzymes such as superoxide dismutase (SOD) and catalase (CAT) in both the algal cells. Furthermore, morphological changes like cell aggregation and surface chemical changes in the algae were ascertained by optical microscopy and FTIR spectroscopy techniques, respectively. The tests confirmed that Scenedesmus obliquus was more sensitive than Chlorella sp. to the mask leachates. Our study clearly revealed serious environmental risk posed by the released microplastics from surgical face masks. Further work with other freshwater species is required to assess the environmental impacts of the mask leachates.

Exudation of microplastics from commonly used face masks in COVID-19 pandemic.

The COVID-19 pandemic forced use of face masks up to billions of masks per day globally. Though an important and necessary measure for control of the pandemic, use of masks also poses some inherent risks. One of those risks is inhalation of microplastics released from the mask materials. Since most of the mask materials are made from plastic/polymers, they always have the potential to expose the user to fragmented microplastics. To estimate the amount of inhalable microplastic exuded from masks, an experiment simulating real-life scenario of mask usage was performed. The study included collection of microplastics oozed out from the masks on to a filter paper followed by staining and fluorescence detection of the total number of microplastics using a microscope. Both used and new masks were studied. Based on the emission wavelength, the microplastics were found to be belonging to three different categories, namely blue, green and red emitting microplastics respectively. The number of microplastic particles emitted per mask over a period of usage of 8 h was about 5000 to 9000 for new masks and about 6500 to 15,000 for used masks respectively. The estimation of polymer type of plastic in the mask fabrics was also carried out using Raman and FTIR spectroscopy.

Association between Microorganisms and Microplastics: How Does It Change the Host-Pathogen Interaction and Subsequent Immune Response?

Plastic pollution is a significant problem worldwide because of the risks it poses to the equilibrium and health of the environment as well as to human beings. Discarded plastic released into the environment can degrade into microplastics (MPs) due to various factors, such as sunlight, seawater flow, and temperature. MP surfaces can act as solid scaffolds for microorganisms, viruses, and various biomolecules (such as LPS, allergens, and antibiotics), depending on the MP characteristics of size/surface area, chemical composition, and surface charge. The immune system has efficient recognition and elimination mechanisms for pathogens, foreign agents, and anomalous molecules, including pattern recognition receptors and phagocytosis. However, associations with MPs can modify the physical, structural, and functional characteristics of microbes and biomolecules, thereby changing their interactions with the host immune system (in particular with innate immune cells) and, most likely, the features of the subsequent innate/inflammatory response. Thus, exploring differences in the immune response to microbial agents that have been modified by interactions with MPs is meaningful in terms of identifying new possible risks to human health posed by anomalous stimulation of immune reactivities.

Multigenerational effects of microplastic fragments derived from polyethylene terephthalate bottles on duckweed Lemna minor: Size-dependent effects of microplastics on photosynthesis.

The 2019 global coronavirus disease pandemic has led to an increase in the demand for polyethylene terephthalate (PET) packaging. Although PET is one of the most recycled plastics, it is likely to enter the aquatic ecosystem. To date, the chronic effects of PET microplastics (MPs) on aquatic plants have not been fully understood. Therefore, this study aimed to investigate the adverse effects of PET MP fragments derived from PET bottles on the aquatic duckweed plant Lemna minor through a multigenerational study. We conducted acute (3-day exposure) and multigenerational (10 generations from P0 to F9) tests using different-sized PET fragments (PET0-200, < 200 µm; PET200-300, 200-300 µm; and PET300-500, 300-500 µm). Different parameters, including frond number, growth rate based on the frond area, total root length, longest root length, and photosynthesis, were evaluated. The acute test revealed that photosynthesis in L. minor was negatively affected by exposure to small-sized PET fragments (PET0-200). In contrast, the results of the multigenerational test revealed that large-sized PET fragments (PET300-500) showed substantial negative effects on both the growth and photosynthetic activity of L. minor. Continuous exposure to PET MPs for 10 generations caused disturbances in chloroplast distribution and inhibition of plant photosynthetic activity and growth. The findings of this study may serve as a basis for future research on the generational effects of MPs from various PET products.

Weathering and degradation of polylactic acid masks in a simulated environment in the context of the COVID-19 pandemic and their effects on the growth of winter grazing ryegrass.

The COVID-19 pandemic has led to explosive growth in the production and consumption of disposable medical masks, which has caused new global environmental problems due to the improper disposal of these masks and lack of effective mask recycling methods. To reduce the environmental load caused by the inability of synthetic plastics to degrade, polylactic acid (PLA) masks, as a biodegradable environmentally friendly plastic, may become a solution. This study simulated the actual degradation process of new PLA masks in different environments by soaking them in various solutions for 4 weeks and explored the influence of the treated PLA fabric fibers on the growth of winter ryegrass. The results show that the weathering degradation of PLA fibers in water mainly occurs through the hydrolysis of ester bonds, and weathering leads to cheese-like and gully-like erosion on the surface of the PLA fiber fabric layer and finally to fiber fracture and the release of microplastics (MPs). The average number of MPs released within 4 weeks is 149.5 items/piece, the particle size is 20-500 µm (44%), and 63.57% of the MPs are transparent fibers. The outer, middle, and inner layers of weathered PLA masks tend to be hydrophilic and have lower mechanical strength. PLA fibers after different treatment methods affect the growth of winter ryegrass. PLA masks are undoubtedly a greener choice than ordinary commercial masks, but in order to confirm this, the entire degradation process, the final products, and the impact on the environment need to be further studied. In the future, masks may be developed to be made from more environmentally friendly biodegradable materials that can have good protecting effects and also solve the problem of end-of-life recycling. A SYNOPSIS: Simulation of the actual degradation process of PLA masks and exploration of the influence of mask degradation on the growth of winter ryegrass.

Microplastics: A Real Global Threat for Environment and Food Safety: A State of the Art Review.

Microplastics are small plastic particles that come from the degradation of plastics, ubiquitous in nature and therefore affect both wildlife and humans. They have been detected in many marine species, but also in drinking water and in numerous foods, such as salt, honey and marine organisms. Exposure to microplastics can also occur through inhaled air. Data from animal studies have shown that once absorbed, plastic micro- and nanoparticles can distribute to the liver, spleen, heart, lungs, thymus, reproductive organs, kidneys and even the brain (crosses the blood-brain barrier). In addition, microplastics are transport operators of persistent organic pollutants or heavy metals from invertebrate organisms to other higher trophic levels. After ingestion, the additives and monomers in their composition can interfere with important biological processes in the human body and can cause disruption of the endocrine, immune system; can have a negative impact on mobility, reproduction and development; and can cause carcinogenesis. The pandemic caused by COVID-19 has affected not only human health and national economies but also the environment, due to the large volume of waste in the form of discarded personal protective equipment. The remarkable increase in global use of face masks, which mainly contain polypropylene, and poor waste management have led to worsening microplastic pollution, and the long-term consequences can be extremely devastating if urgent action is not taken.

Polypropylene nanoplastic exposure leads to lung inflammation through p38-mediated NF-κB pathway due to mitochondrial damage.

BACKGROUND: Polypropylene (PP) is used in various products such as disposable containers, spoons, and automobile parts. The disposable masks used for COVID-19 prevention mainly comprise PP, and the disposal of such masks is concerning because of the potential environmental pollution. Recent reports have suggested that weathered PP microparticles can be inhaled, however, the inhalation toxicology of PP microparticles is poorly understood. RESULTS: Inflammatory cell numbers, reactive oxygen species (ROS) production, and the levels of inflammatory cytokines and chemokines in PP-instilled mice (2.5 or 5 mg/kg) increased significantly compared to with those in the control. Histopathological analysis of the lung tissue of PP-stimulated mice revealed lung injuries, including the infiltration of inflammatory cells into the perivascular/parenchymal space, alveolar epithelial hyperplasia, and foamy macrophage aggregates. The in vitro study indicated that PP stimulation causes mitochondrial dysfunction including mitochondrial depolarization and decreased adenosine triphosphate (ATP) levels. PP stimulation led to cytotoxicity, ROS production, increase of inflammatory cytokines, and cell deaths in A549 cells. The results showed that PP stimulation increased the p-p38 and p-NF-κB protein levels both in vivo and in vitro, while p-ERK and p-JNK remained unchanged. Interestingly, the cytotoxicity that was induced by PP exposure was regulated by p38 and ROS inhibition in A549 cells. CONCLUSIONS: These results suggest that PP stimulation may contribute to inflammation pathogenesis via the p38 phosphorylation-mediated NF-κB pathway as a result of mitochondrial damage.

Post-pandemic micro/nanoplastic pollution: Toward a sustainable management.

The global health crisis caused by the COVID-19 pandemic has resulted in massive plastic pollution from the use of personal protection equipment (PPE), with polypropylene (PP) being a major component. Owing to the weathering of exposed PPEs, such contamination causes microplastic (MP) and nanoplastic (NP) pollution and is extremely likely to act as a vector for the transportation of COVID-19 from one area to another. Thus, a post-pandemic scenario can forecast with certainty that a significant amount of plastic garbage combined with MP/NP formation has an adverse effect on the ecosystem. Therefore, updating traditional waste management practices, such as landfilling and incineration, is essential for making plastic waste management sustainable to avert this looming catastrophe. This study investigates the post-pandemic scenario of MP/NP pollution and provides an outlook on an integrated approach to the recycling of PP-based plastic wastes. The recovery of crude oil, solid char, hydrocarbon gases, and construction materials by approximately 75, 33, 55, and 2 %, respectively, could be achieved in an environmentally friendly and cost-effective manner. Furthermore, the development of biodegradable and self-sanitizing smart PPEs has been identified as a promising alternative for drastically reducing plastic pollution.

Analysis of Marine Microplastic Pollution of Disposable Masks under COVID-19 Epidemic-A DPSIR Framework.

Marine microplastic pollution (MMP) is becoming one of the most pressing environmental problems facing humanity today. The novel coronavirus epidemic has raised the issue of environmental contamination caused by large-scale improper disposal of medical waste such as disposable masks (DMs). To assess the impact of MMP caused by DMs and to seek solutions for the prevention and control of MMP, this study uses the Driving force-Pressure-State-Impact-Response (DPSIR) framework to establish a causal chain of MMP caused by DMs. The conclusion shows that the novel coronavirus epidemic has led to a surge in the use of DMs, which has brought pressure on resource constraints and environmental pollution at the same time. Improperly DMs enter the environment and eventually transform into MMP, which not only endangers the marine ecological system but also poses potential human health risks as well as economic and social hazards. In addition, further research on environmentally friendly masks (cloth masks and biodegradable masks) is essential to mitigate the environmental damage caused by the large-scale global use of DMs. This study provides a scientific and theoretical basis for the assessment of MMP from discarded DMs, and the findings of this study will provide a reference for the formulation of relevant policies.

Environmental risks due to the presence of microplastics in coastal and marine environments of the Colombian Caribbean.

Microplastics (MPs) are plastic sediments that are released into the environment by various sources, their abundance and distribution increase as their size decreases, they represent a risk to ecological processes and their abundance is related to their proximity to human activities and The Anthropocene era, in addition to the Covid-19 pandemic, has exacerbated the emitting sources of plastics such as face masks, disinfectant container bottles, among others, all due to all the biosafety measures required globally. Over time, the transformation of plastics into microplastics generates particles transported by atmospheric and water dynamics, being accumulated in soils, bodies of water and incorporated into ecosystems and the food chains of organisms, including humans. Marine-coastal environments such as coastal lagoons, which in addition to hosting strategic ecosystems, being areas of convergence of different ecological flows and with important ecosystem services, have also become sinks for MP particles, putting their productivity and value at risk. Socio-ecological that they have. The purpose of this research is to evaluate and zone the environmental risks derived from contamination by microplastics in a coastal lagoon system, since once the MPs enter the environment they can cause harmful effects, in this case in the Caribbean Sea and in the lagoon complex. To this end, a comprehensive study of planetary systems was carried out to better understand their disturbances due to the presence of microplastics.

A review of disposable facemasks during the COVID-19 pandemic: A focus on microplastics release.

The COVID-19 epidemic seriously threats the human society and provokes the panic of the public. Personal Protective Equipment (PPE) are widely utilized for frontline health workers to face the ongoing epidemic, especially disposable face masks (DFMs) to prevent airborne transmission of coronavirus. The overproduction and massive utilization of DFMs seriously challenge the management of plastic wastes. A huge amount of DFMs are discharged into environment, potentially induced the generation of microplastics (MPs) owing to physicochemical destruction. The MPs release will pose severe contamination burden on environment and human. In this review, environmental threats of DFMs regarding to DFMs fate in environment and DFMs threats to aquatic and terrestrial species were surveyed. A full summary of recent studies on MPs release from DFMs was provided. The knowledge of extraction and characterizations of MPs, the release behavior, and potential threats of MPs derived from DFMs was discussed. To confront the problem, feasible strategies for control DFMs pollution were analyzed from the perspective of source control and waste management. This review provides a better understanding the threats, fate, and management of DFMs linked to COVID-19 pandemic.

Microbial strategies for degradation of microplastics generated from COVID-19 healthcare waste.

COVID-19 pandemic has led to the generation of massive plastic wastes, comprising of onetime useable gloves, masks, tissues, and other personal protective equipment (PPE). Recommendations for the employ of single-use disposable masks made up of various polymeric materials like polyethylene, polyurethane, polyacrylonitrile, and polypropylene, polystyrene, can have significant aftermath on environmental, human as well as animal health. Improper disposal and handling of healthcare wastes and lack of proper management practices are creating serious health hazards and an extra challenge for the local authorities designated for management of solid waste. Most of the COVID-19 medical wastes generated are now being treated by incineration which generates microplastic particles (MPs), dioxin, furans, and various toxic metals, such as cadmium and lead. Moreover, natural degradation and mechanical abrasion of these wastes can lead to the generation of MPs which cause a serious health risk to living beings. It is a major threat to aquatic lives and gets into foods subsequently jeopardizing global food safety. Moreover, the presence of plastic is also considered a threat owing to the increased carbon emission and poses a profound danger to the global food chain. Degradation of MPs by axenic and mixed culture microorganisms, such as bacteria, fungi, microalgae etc. can be considered an eco-sustainable technique for the mitigation of the microplastic menace. This review primarily deals with the increase in microplastic pollution due to increased use of PPE along with different disinfection methods using chemicals, steam, microwave, autoclave, and incineration which are presently being employed for the treatment of COVID-19 pandemic-related wastes. The biological treatment of the MPs by diverse groups of fungi and bacteria can be an alternative option for the mitigation of microplastic wastes generated from COVID-19 healthcare waste.

Porous charged polymer nanosheets formed via microplastic removal from frozen ice for virus filtration and detection.

We developed a method for producing porous charged polymer nanosheets using frozen ice containing microplastics. Upon assessing SARS-CoV-2 filtration using nanosheets with 100 nm-sized pores, a high rejection rate of 96% was achieved. The charged surfaces of nanosheets further enabled the electrophoretic capture of the virus using a portable battery with additional real-time sensing capability.